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    // for in 遍历对象
    var arry = ['a', 'b', 14]
    var person = { name: '张三', age: 18, 年纪: '20级' }
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    for (let x in person) {
      y += person[x] + " ";
    }
    console.log(y)
    // for of 迭代对象的值
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